In earlier studies, we described immunocytochemical changes in basement membrane (BM) components of myofibers and Schwann cells after transplantation injury in rats. We speculated that the loss of BM components might be important in permitting myosatellite and Schwann cells to detach from their BM and to proliferate and migrate. In order to determine whether degradation of Schwann cell BM influenced axonal regeneration, we froze normal or predegenerated (8-weeks post axotomy) nerve autografts (4 cm long) prior to transplantation. Freezing was intended to kill Schwann, vascular and perineurial cells in the graft leaving behind unchanged (normal nerve) or degradated (predegenerated nerve) BM tubes. After 3 months, we found no significant axonal regeneration through either type of frozen nerve graft. This finding supports our contention that viable cells, and not BM alone, are required for axonal growth through long nerve grafts. To further examine the role of extracellular matrix in regeneration, we applied fluorescein-conjugated lectins, to tissue sections of autografts of regenerating skeletal muscle. We found an intense binding of wheat germ agglutinin (WGA) to the myogenic zone of regenerating muscle. Since WGA binds specifically to N-acetylglucosamine, this binding may mean that an N-acetylglucosamine-rich environment is favorable for myosatellite activation, proliferation and fusion to form myotubes. We are currently in the process of using labelled lectins to study nerve and taste bud regeneration.